Fuel nozzle



Dec. l, 1931.

W. F. JOACHIM FUEL NOZZLE Filed April 50, 1930 M501 nukousz. Just, 5 /jMl NYI wlTNEss 6.1113;

I Patented Dec. 1, 1931 UNITED STATES PATENT OFFICE WILLIAM F. JOACHIM,OF RIDLEY PARK, PENNSYLVANIA, ASSIGNOR TO WESTINGHOUSE ELECTRIC &MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA FUEL NOZZLEApplication filed April 30, 1930. Serial No. 448,710.

My invention relates to injection valves or atomizers, more particularlyto valves forinjecting fuel into the cylinders of internal combustionengines and still more particularly to valves which are especiallysuitable for use with fuel injection systems of the hydraulic I pressureinjection type, that is, systems wherein the fuel is injected into theengine cylinder by mechanical means, such as a io plunger pump, at arelatively high pressure and at an extraordinarily rapid rate. My

invention has for an object to provide apparatus of the characterdesignated which shall be capable of so injecting the fuel as to producelower maximum Working pressures within the engine cylinder, increase thecombustion efficiency obtaining in the engine cylinder and,consequently, lower the fuel consumption of the engine, as well asincrease the :o mean effective pressure obtaining in the engine cylinderand, consequently, increase the horse power rating of the engine.

These and other objects are effected by my invention as will be apparentfrom the following description and claims taken in connection with theaccompanying drawings, forming a part of this application, in which:

Fig. 1 is a graphic diagram of the process of injecting fuel into thecylinder of an internal combustion engine;

Fig. 2 is a view, in sectional elevation, of one form of injection valveor atomizer arranged in accordance with my invention; and,

Fig. 3 is an enlarged, partial, sectional view of the tip portion of theinjection valve shown in Fig. 2.

As is well understood in the internal combustion engine art, a fuelinjection system of the hydraulic pressure injection type normallyembodies, essentially, a fuel injection pump which is usually of theplunger type and supplied with fuel at a positive but relatively lowpressure by a booster pump or supply tank. The fuel injection pump isdriven 4' in timed relation With the crank shaft of the engine and hassome form of valve means associated therewith capable of rendering thepump periodically effective to discharge the fuel to the injection valveat a relatively high pressure. The fuel injection Valve is usually soarranged that it opens periodically in response to the successivedischarges of the inj ection pump and the valve serves to atomize thefueland to deliver the same into the combustion chamber of the engine.Such systems must. be very carefully constructed and arranged in view ofthe extraordinary requirements in that the pump may be required toperiodically and almost instantly develop a pressure as high as 8,000 ormore pounds per square inch and to deliver an accurately meteredquantity of fuel consistently as required. By way of example, an enginehaving a nine-inch bore. and a twelve-inch stroke may require theperiodic delivery, during approximately .003 of a second, ofapproximately .034 cubic inches of fuel. These iigures demonstrate withwhat exactitude the fuel must be metered and delivered to the. engineduring each cycle thereof.

As stated heretofore, the fuel injection valve delivers the fuel,received from the injection pump, to the combustion chamber of theengine cylinder. I have found that the combustion eiiciency obtaining inthe engine cylinder is vitally affected by the manner in which the fuelvalve delivers the fuel to the combustion chamber.

In determining the proper action of the fuel injection valve, it hasheretofore been customary to take into consideration the amount of workto be performed in a given size of engine cylinder. the. form of thecombustion chamber, etc. However, if good combustion efficiency is to beobtained, additional fac-tors must be taken into consideration andcalculated. Among others, the following factors are given by way ofexample:

(l) The changing position of the mass center of the air which is undercompression by the piston in the combustion chamber as effected by themovement of the piston. In vthe resent example, the mass center of theair or every five degrees crank angle position of the piston before andafter top center during the fuel spray development and the air mix-ingprocess have been taken into conf sideration. V

A with which it must later mix and burn.

(b) Distribution lag which is the time re quired for the fuel to mixwith its air after it has penetrated the required distance into thecombustion chamber.

(c) Ignition lag which is the time required for thevapor from any fuelparticle to become ignited; and,

- Combustion lag which is the time required' for any fuel particle to becompletely vapor-ized and burned.

(3) Coordination of the varying quantities 'of fuel being distributedwith the changing position of the air mass center.

As aresult of analyses including the foregoing, as Well as manyadditional conditions,

I have found that the fuel should be injected at a vgreatly acceleratedrate.

into the engine cylinder approximately as indicated in Fig. 1 in whichthe angular positions of thc crank shaft before and after top center areindicated'as abscissa and the rate of fuel injection as ordinates. Fromthe curve indicated by reference character A, it will be apparent that,in the present example, fuel injection should commence at a position ofapproximately 35 before top center, depending on engine speed. This rateshould then slowly increase until a crank angle approximately 10 beforetop center is reached, depending on engine speed, when the quantity offuel injected should increase This curve shows that, in order to obtainthe best combustion efficiency in a Diesel engine, the rate of fuelinjection at the start of each cycle must be relatively slow but rapidlyaccelerated'near the end of the injection cycle.

Injection of fuel in a manner such as described can not be obtained withfuel injection valves of the character heretofore ernployed, becausethese injection valves generally comprise a single fuel passage ornozzle, or a single set of nozzles acting in unison, controlled by asingle valve stem' opened by the fuel pressure delivered by theinjection pump against the force exerted by a single spring.Consequently. instead of obtaining a rate of injection approximating thecurve A, a rate of injection corresponding to an approxmately straightline is obta' ,h straight line characteristic cannot oe so inclined asto very closely curve A, Consequent relatively poor combustionefficiency has geen obtained with the types of injection valvesheretofore employe I have, therefore, conceived the idea of providing aninjection valve of, what may be termed, .the multiple orifice or nozzlet in which the orifices or nozzles have indivldual valve mechanismsassociated therewith which open in response to different fuel pressures,the first or primary orifice or nozzle providing for the early andrelatively slow rate of fuel injection and the second or secondaryorifice or nozzle being effective, during the latter portion of the fuelinjection period, to augment the action of the primary orifice or nozzleso as to provide for a relatively rapid rate of fuel injection duringthe latter portion of each injection period. By means of such a form ofinjection valve, an injection characteristic such as indicated by thecurve B, in Fig. 1' is obtainable, the action of the primary orifice ornozzle being indicated by the portion B of the curve while the action ofboth orifices or nozzles is indicated by the portion B of the curve.From inspection of Fig. 1, it will be apparent that the curve B closelyapproximates the theoretically ideal curve A and, furthermore, it willbe apparent that, by employing more than two orifices or nozzles withsuitable stems, springs, fuel passages, etc., even a closerapproximation can be had.

It is, therefore, a still more particular object of my invention toprovide a form of injection valve which is capable of so delivering thefuel into the combustion chamber during each injection period as to soaccelerate the rate of fuel delivery as to obtain nearly idealcombustion conditions.

Referring now to the drawin I show, in Figs. 2 and 4, a cylinder 10 o aninternal combustion engine. The cylinder 10 is provided with aprojecting portion 11 which forms a receptacle for a fuel injectionvalve, generally represented at 12. An opening 13 communicates with theinterior of the cylinder 10, the opening being preferably provided witha counterbore 14 forming a shoulder 15. Fitting within the opening 13and seated upon the shoulder 15 is a nozzle 16 having a conical faceportion 17 terminating in a centrally-disposed tip 18. The nozzle 16 isprovided with an inner conical seat 19 upon which is seated a seat piece21, the latter being provided with an inner conical seat 22. Extendingtoward the seat iece 21 is a secondary valve stem 23 provide with avalve face 24 which coacts with the seat 22 of the seat piece. Thesecondary valve stem 23 is provided with a shoulder or piston portion 25spaced axially fronr the valve face.

approximate the Surrounding the secondary valve stem 23 is an annular,prilnary valve stem 2G provided with an annular valve face 27 which alsocoacts with the seat 22 of the seat piece. The primary 'alve stem 26 isalso provided with a. shoulder or piston portion 28 spaced axially fromits valve face. Provided axially within the seat piece and the nozzle isa lsecondary fuel passage 29 arranged to be opened and closed bymovementof the secondary valve stem 23. Secondary fuel from the passage29 is atomized and sprayed into the engine cylinder by a plurality oforifices of such size and spacing as to correctly deliver fuel for thesecondary injection. In the present embodiment` I show one form of a1"-rangement wherein there is provided a plurality of upper,circumferentially-spaced and radially-extending orifices 31 and aplurality of lower, circumferentially-spaced and somewhatdownwardly-inelined and diverging orifices 32. Provided in the seatpiece 21 between the valve faces 24 and 27 are a plurality ofcircumferentially-spaced, and somewhat downwardly-inclined holes 33which communicate, with primary orifices 34 also provided in the nozzle.The primary orifices 34 and the secondary orifices 31 are preferably soinclined with respect to each other as to direct the conical fuel sprayfrom the secondary orifices 31 in a plane intersecting the conicalprim-ary fuel spray emitted from the primary orifices 34 though thisfeature may be arranged to suit the special requirements of the engineconsidered.

The seat piece. and the nozzle areretaincd in relative posit-ion by anatomizer body 41. The nozzle surrounds the atomizer body and is securedthereto by screw threads 42, the nozzle serving to clamp the seat piecewithin the atomizer body by thrusting its shoulder portion 43 againstthe lower lateral end face of the atomizer body. The seat piece may alsobe a press fit in the atolnizer body. Disposed in abutting relation withthe upper lateral face 43 of the atomizer body is a nut 44 having anexternal, flat-sided portion -l--l and held in position in thereceptacle ll by a clamp 45. The latter engages the nut 44 by means ofscrew threads 45 and is detaclnibly secured to the engine cylinder bysome means, such as. for example. a tap bole 46.

The atomizer body is provided with a lower bore 47 and with an uppercounterbore 48, the two bores being joined by an internal conical seat49. Seated in the latter is a flange portion 51 of a guide bushing 51.The latter projects downwardly within the nozzle body and terminatesnear the vicinity of the seat piece 21. The. guide bushing 51 has areduced diametral portion 52 and one or more slots or flats which form,with the bore 47 of the body member, an intervening passage 53 arrangedto receive fuel delivered through an inlet 54 and to transmit the sameto the shoulder or piston face 28 (Fig. 3) of the primary valve stem andto theI shoulder or plston face 25 of the secondary valve stem at suchtimes as the primary valve stem is in'open position.

The bushing 51 is held in abutting relation with the seat 49 by means ofa sleeve 55 screwed into the counter-bore 48 of the nozzle body andabutting, through a distance piece 57, with the upper lateral face 58 ofthe guide bushing. The sleeve is bored out to provide a housing for acompression spring 59 which engages the primary valvestem 26 through aspring carrier 61 freely carried on the upper end of the primary valvestem. The upper end portion of the spring exerts its thrust against ashoulder (52 of the bushing and, preferably interposed between thespring 59 and the shoulder 62, are one or lnore shims or distance pieces63 for effecting adjustments of the spring force. The spring 59 servesto hold the primary valve stem 26 to a closed position, that is, theposition indicated in Fig. 3. The bore of the distance piece 57 is maderelatively larger than the bore of the adj accnt end of the sleeve 55 soas to provide a shoulder 60 which coacts with the spring carrier 61 tolimit opening movements of the primary valve stem 26.

The upper end of the secondary valve stem 23 is also provided with aspring carrier 64 and a compression spring 65, the latter being retainedin the sleeve by a nut 66 threaded tio the sleeve, as at 66. Fittingbetween the spring and the nut 66 are one or more shims or distancepieces 67 for effecting adjustments of the spring 65. As will beapparent, the spring G5 serves to hold the secondary valve stem 23 to aclosed position, that is, the position indicated in Fig. 3. The lift ofthe secondary valve stem 23 is limited by a stop (39 which depends fromthe nut G6 and coacts with the spring carrier 64. Fuel which lnay leakbetween the relatively movable primary and secondary valve stems as wellas the primary valve stem and the guide bushing is relieved through anoutlet 71 provided in the nut 66 and having a threaded portion 72 forconnecting a drain conduit thereto (not shown).

The operation of the foregoing fuel injection nozzle will now bedescribed. Let it be assumed that fuel is being periodically disihargedat a high pressure to the inlet 54 by suitable. pumping apparatus in amanner well understood in the art. The fuel pressure is transmitted fromthe inlet 54 through the space 53 intervening between the bushing 51 andthe atomizer body 41 as well as the communicating annular space 73intervening between the primary Yalve stem 26 and the seat piece 21 andis imposed upon the shoulder or piston face 28 of the primary valve stem2G. lVhen the fuel pressure rises sufliciently, the force exerted by thespring 59 is overcome and the primary valve stem 26 is raised,permitting fuel to be discharged throu h the primary passages 33 andprlmary ori ces 34 into the engine cylinder. The opening movement of thepr1mary valve stern 26 is accurately limited by the spring carrier 61abutting against the shoulder 60.

After the primary valve stem has opened and primary fuel is beingsprayed into the engine cylinder by the primary orifices 34,

the increasing pressure of the fuel deliveredby the pump isimposed uponthe piston face or shoulder 25 of the secondary valve stem 23 and, uponsufficient increase in pressure over and Aabove that which raised theprimary valve stem 26, the force of the spring is overcome and thesecondary valve stem 23 is raised to permit fuel to enter the passageway29 and to be sprayed into the cylinder through the secondary orifices 31and 32. The opening movement of the secondary valve stem 23 isaccurately limited by the spring carrier 64 coming into abuttingrelation with the stop 69. As soon as the fuel pressure in the inlet 54falls, both springs 59 and 65 act to close their associated valve stemsand injection of fuel into the engine cylinder is momentarilyinterrupted until such time as 'the fuel pressure in the inlet 54 isagain raised. Y

From the foregoing, it will be apparent that the primary fuel sprays,that is, the sprays discharged through the primary orifices 34 enter theengine cylinder before or ahead of the secondary sprays, thatis, thefuel sprayed into the cylinder through the secondary orifices 31 and 32.In the present embodiment, this is accomplished by utilizing suchsprings and primary stem and secondary stem lifting faces 25 and 28,respectively, as together Will cause the primary stem to lift e at someparticular higher unit fuel pressure as is required by the engine andfuel pump under consideration. For example, the spring associated withthe primary valve stem in combination with the primary stem lifting face28 may be so proportioned as to require a unit fuel pressure of 1800lbs. per sq. inch to cause the" primary stem to lift while the springassociated with the secondary valve stem in combination with thesecondary stem lifting face 25 may require a unit fuel1 pressure of 3000lbs. per sq. inch to cause the secondary stem to lift.

The primary fuel sprays or orifices 34 preferably have a lesser flowcapacity than the secondary orifices 31 and 32 so that the pri maryorifices first deliver a relatively small quantity of fuel at arelatively slow rate to the engine cylinder, and, after a predeterminedperiod, the secondary valve opens to rapidly accelerate the delivery offuel. as generally indicated by curve B in Fig. 1. In this connection,it is noted that the capacity of the primary orifices 34 is relativelylower than the rate of fuel delivery through the inlet 54 so that, eventhough the primary orlfices 34 are spraying fuel into the enginecylinder, the fuel pressure at such times is lncreasing so as to causesubsequent opening of the secondary valve stem.

A form of injection nozzle of the character disclosed effects a processof combustion within the cylinder which is such as to both lower themaximum working pressure and to increase the combustion efficiency andconsequently the horse power rating of the engine cylinder. Inaccordance with this process, the primary fuel spray enters the cylinderahead of the secondary fuel sprays and are normally already burning whenthe secondary fuel sprays enter the engine cylinder. It should beunderstood that the processes of this combustion system may be carriedout as well in certain cases where the primary sprays need not beactually burning before the secondary sprays enter the engine cylinderbut said primary sprays must ignite shortly after the secondary spraysenter the engine cylinder and before the said secondary sprays ignitedue to the heat of compression of the cylinder air. The primary fuelsprays serve to uniformly and progressively increase the temperature andpressure obtaining Within the combustion chamber of the cylinder. and,inasmuch as the primary injection and combustion generally take placewhile the engine piston is approaching its top center position, idealtemperature and pressure conditions are produced in the engine cylinderby the time the secondary fuel sprays are admitted. At the time theprimary sprays are admitted to the combustion chamber, there is anabundance of air in the combustion chamber in proportion to the amountof fuel admitted so'that the primary sprays burn easily and efficiently.In addition, because of the limited quantity of fuel in the rimarysprays, which is approximately oneourth to one-sixth the full load fuelquantity, knocking is avoided.

When the primary fuel sprays are burning, there is local heating of theair in the immediate vicinity of the primary fuel sprays. This heatedair naturally expands and serves to compress the relatively cool gas inthe remaining or more distant portions of the combustion chamber. Inother words, the air which is heated in the vicinity of the prima ryfuel sprays serves. when it expands, as a fluid piston to force a largeportion of the remain- 1 ing air in the combustion chamber away from theburning primary fuel spray toward tlvl remote portions of the combustionchamber As a result, adiabatic compression of that portion of the air inthe combustion chamber assigned to the secondary fuel sprays is effectedprior to the entry of the secondary fuel spray. This adiabaticcompression further prepares the air for more rapid ignition andprogressive and complete combustion of the secondary fuel sprays byincreasing both the temperature and density of the cylinderl air. Ofadditional importa-nce is the fact that this compression process createsconsiderable turbulence of the air within the combustion chamber priorto and during the admission of the secondary fuel spray. Furthermore,when the-secondary fuel spray is admitted to the engine cylinder, itignites easily and early because an ignition flame is already providedby the burning primary fuel spray.

As will be apparent from Figs. 2 and 3, the secondary orifices 31 are soinclined, in relation to the primary orifices 34 that the fuel sprayadmitted through the orifices 31 intersects the primary fuel spray. Thesecondary fuel spray is therefore progressively ignited by the primaryfuel spray.

At commencement of the secondary fuel spray, the air is concentrated inthe head end of the cylinder because of the fact that the piston is nearits top center position. However, as the pistons move away from the headortion of the cylinder on its working or firing stroke, the air in thecombustion chamber is expanded and circulation toward the moving pistonis effected. As a result, the air is drawn through the heavy fuelparticles discharged from the secondary orifices 31 and 32 andthoroughly commingled therewith.

From the foregoing, it will be apparent that I have evolved a form ofinjection nozzle which is capable of producing, in the cylinder of aninternal combustion engine, a combustion process of a new and improvedcharacter and capable of producing more efficient combustion of fuelthan the systems heretofore provided. While, in the present embodiment,I show a form of injection nozzle in which the primary and secondaryorifices as well as the primary and secondary valve stems are arrangedco-aXially, nevertheless, it will be apparent that other arrangementsmay be utilized as my invention contemplates, in its broader aspects,the provision of fuel injection apparatus for an engine cylinder whichis capable of so regulating the supply of fuel into the engine cylinderas to provide a relatively slow rate of fuel delivery during the earlyportion of each injection period and a rapidly accelerated rate of fuelinjection during the latter portion of each injection period.

lVhile I have shown my invention in but one form, it will be obvious tothose skilled in the art that it is not so limited, but is susceptibleof various changes and modifications, without departing from the spiritthereof, and I desire, therefore, that only such limitations shall beplaced thereupon as are imposed by the prior art or as are specificallyset forth in the appended claims.

That I claim is 1. In fuel injection apparatus for the cylinder of aninternal combustion engine, the combination of nozzle means having firstand second spray openings, valve means for controlling the flow of fuelthrough the first and second spray openings, and means responsive tofuel pressure for opening the first and second valve means successivelyso as to provide an accelerated rate of fuel ldelivery into the enginecylinder.

2. In apparatus for periodically linjecting fuel into the cylinder of aninternal combustion engine, the combination of nozzle means having arelatively small capacity primary nozzle opening and a relatively largercapacity secondary nozzle opening, valve means for controlling the flowof fuel through each nozzle opening, and means responsive to fuelpressure for opening the Aprimary valve means and subsequently thesecondary valve means so asto provide an acceleration in the rate offuel delivery into the engine lcylinder during an intermediate portionof each injection period.

3. In fuel injection apparatus for the cylinder of an internalcombustion engine, the combination of nozzle means having primary andsecondary orifices, valve means associated with the respective orificesfor controlling the flow of fuel therethrough, and means responsive toan increase in fuel pressure for opening the primary and secondary valvemeans in sequence and responsive to a decrease in fuel pressure forclosing them simultaneously.

4. In fuel injection apparatus for the cyl- 100 inder of an internalcombustion engine, the combination of nozzle means having a series ofnozzle openings of progressively increasmg capacities, Valve meansassociated with the respective nozzle openings for control- 105 ling theflow of fuel therethrough, and means responsive to increases in fuelpressure for opening the valve means progressively so as to provide forrapid acce-leration in the rate of fuel delivery into the enginecylinder dur- 110 ing the injection period.,

5. In apparatus for periodically injecting fuel into the cylinder of aninternal combustion engine, the combination of nozzle means having firstand second spray openings, sepa- 5 rate valve means associated with thefirst and second spray openings for controlling the flow of fueltherethrough, said first and second valve means being disposed inconcentric relation, and means responsive to 120 increases in fuelpressure for opening the primary valve means and subsequently thesecondary valve means so as to provide an acceleration in the rate offuel delivery into the engine cylinder during an intermediate 125portion of each injection period.

6. In fuel injection apparatus for the cylinder of an internalcombustion engine, the combination of nozzle means havingconcentrically-arranged first and second circum- 130 ferentially spacedspray openings, separate valve means associated with the first andsecond spray openings for controlling the flow of fuel therethrough,said first and second valve means being disposed in' concentricrelation, means for biasing the respectlve valve means to closedpositions, means responsive to fuel pressure for opening the primaryvalve means and means responslve to a substantially greater fuelpressure for opening the secondary valve means.

7. In a fuel injection apparatus for the c linder of an internalcombustion engine, t e combination of a plurality of circumferentiall -saced orifices for discharging primary e and having their respective axesdisposed in conical formation, additional circumferentially-disposedorifices disposed interiorly of the primary orifices for dischargingsecondary fuel, said secondary orifices having their axes intersectmgthe cone formed by the axes of the primary orifices, valve meansassociated with the primary and secondary orifices for controlling theflow of fuel therethrough, means responsive to an increase in fuelressure for actuating the valve means to ischarge fuel through theprimary orifices and means responsive to a further increase in fuelpressure for actuating the valve means to discharge fuel through thesecondary orifices.

8. In a fuel injection apparatus for the cylinder of an internalcombustion engine, the combination of a plurality ofcircumferentially-spaced orifices having their respective axes disposedin conical formation for dischargin primary fuel, additional orificesdispose interiorly of the primary orifices for discharging secondaryfuel, said secondary orifices comprising a series ofcircumferentially-spaced orifices having substantiallyradially-extending axes intersecting the cone 'formed by the axes of theprimary orifices and a second series of circumferentiallyspaced orificeshaving their axes defining a cone located interiorly of and spaced fromthe cone defined by the axes of the primary orifices, valve meansassociated with the primary and secondary orifices for controlling theflow of fuel therethrough, means responsive to a predetermined increasein fuel pressure for actuating the valve means to discharge fuel throughthe primary orifices and means responsive to a further increase in fuelpressure for actuating the valve means to discharge fuel through thesecondary orifices.

9. In a fuel injection apparatus for the cylinder of an internalcombustion engine, the combination of a plurality of circumfer`entially-spaced orifices having their respective axes projectingradially outward for discharging primary fuel, a ccnt-rally-disposedaxially-extending fuel passageway, additional circumferentially-spacedorifices communicating with the central passageway and having their axesprojecting radiall outward for the dischar e of secondary fue acentrally disposed, axlally movable valve mechanism cooperating with thecentral fuel passageway for controlling the discharge of fuel by thesecondary orifices, a second valve mechanism disposed concentricallabout the first valve mechanism for controlhng the fiow of fuel throughthe primary orifices, means responsive to a predetermined increase infuel pressure for opening the valve means associated with the primaryorifices, and means responsive to a greater increase in fuel pressurefor opening the valve means associated with the secondary orifices.

l0. In a fuel injection ap aratus for the cylinder of an internal comustion engine, the combination of a nozzle body having an inlet for theadmission of fuel, nozzle means provided in the body, said nozzle meansincluding first and second Spray openings for the discharge,respectively, of primary and secondary fuel, primary valve meansinterposed between the fuel inlet and the primary spray openings forcontrolling the discharge of fuel by the latter, secondary valve meansdisposed on the side of the primary valve means remote from the fuelinlet for controlling the discharge of fuel by the secondary sprayopenings, means responsive to a predetermined increase in fuel pressurefor opening the primary valve means and means res onsive to a furtherincrease in pressure or opening the secondary valve means.

11. In a fuel injection ap aratus for the cylinder of an internal comustion engine, the combination of nozzle means having first and secondspray openings for the discharge of primary and secondary fuel,respectively, separate valve means associated with the first and secondspray openings for controlling the flow of fuel therethrough, meansresponsive to a predetermined increase in fuel pressure for opening theprimary valve means, and means effective upon an opening of the primaryvalve means and responsive to a further increase in fuel pressure foropening the secondary valve means.

12. In fuel injection apparatus for the cylinder of an internalcombustion engine, the combination of a body having an axially extendingopening, a nozzle fitting in said opening. a valve seating memberdisposed within the nozzle` means for admitting fuel to the interior ofthe seating member, primary and secondary spray orifices provided in thenozzle. said seating member having openings extending therethrough forthe passage of fuel to the orifices. a valve'disposed in the seatingmember for controlling the dischargey of fuel through the secondaryorifice, a second valve disposed in the seating member between the firstvalve and the fuel admission means for controlling the discharge of fuelthrough the primary orifice, and means responsive to fuel pressure foropening the valves and providing for opening of the valve controllingthe primary orifice ahead of the valve controlling the secondaryorifice.

13. In a fuel injection device for an intern al combustion engine, thecombination of a body having a fuel inlet, nozzle means secured to thebody and having primary and secondary atomizing means, inner and outerindependently -movable concentric valve members for controlling,respectively, the discharge of fuel from the inlet to the primary andsecondary atomizing means, said inner valve member being longer,axially, than the outer valve member, a spring surrounding the innervalve` member and engaging the outer valve member for biasing the sameto a closed position, a second spring disposed coaxially with the firstspring and engaging the inner valve member for biasing the same to aclosed position, the spring engaging the valve associated with thesecondary atomizing means being formed to exert a greater unit pressurethan the spring engaging the valve associated with the primary atomizingmeans, whereb sequential opening of the valves is aorded, and meansresponsive to the pressure of the fuel admitted through the inlet foropening the valves. r

14. In a fuel injection device for an internal combustion engine, thecombination of a body having a fuel inlet and provided With an axialbore separated by a seat from an interiorly-threaded counterbore, avalve seating member fitting within the end of the bore of the body, anozzle surrounding the body and clamping the seating member thereto,primary and secondary atomizing means embodied in the nozzle, a bushingarranged in said axial bore and having a flange portion fitting the seatof the body, said bushing cooperating with the bore of the body toprovide a passageway from the fuel inlet toward the nozzle, inner andouter concentric valve members movable axially within the bushing andmovable axially with respect to each other for controlling,respectively, movement of fuel from the passageway to the primary andsecondary atomizing means, piston means provided on each of the valvemembers for opening the same in response to fuel pressure,

a sleeve having threads for engagement with the threads of thecounterbore and cooperating with the flange portion of the bushing tomaintain the flange portion of the bushing tightly itted with respect tothe seat of the body portion, said sleeve having a counterbore portionproviding'a shoulder, a compression spring interposed between theshoulder and one of the valve members for biasing the valve member toclosed position, a second spring disposed in the bore of the sleevemember and engaging the other valve member, and a member for closing theend of the sleeve and for retaining the latter spring un-

